Hi Marmuir07, I gather you are referring to importing supported flight plan files into the Navigator app?
There are two ways, one is the default method for all iOS apps. This is by accessing the app Documents folder using the Apple Devices app on Windows, or Finder on macOS.
The second is using the Dropbox Support, which is by no means mandatory. It is included in the app as a convenience for the many who already use that service.